<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style type="text/css">
        span {
            display: block;
            padding: 8px;
            font-size: xx-large;
        }
    </style>
</head>
<body>

text-shadow: red 5px 5px 2px
<span style="text-shadow: red 5px 5px 2px">测试文字</span>

text-shadow: 5px 5px 2px; color:blue;
<span style="text-shadow: 5px 5px 2px; color:blue;">测试文字</span>

text-shadow:-5px -5px 2px gray"
<span style="text-shadow:-5px -5px 2px gray">测试文字</span>

text-shadow:-5px 5px 2px gray
<span style="text-shadow:-5px 5px 2px gray">测试文字</span>

text-shadow:5px -5px 2px gray
<span style="text-shadow:5px -5px 2px gray">测试文字</span>

text-shadow:5px 5px 2px gray
<span style="text-shadow:5px 5px 2px gray">测试文字</span>

text-shadow:15px 15px 2px gray
<span style="text-shadow:15px 15px 2px gray">测试文字</span>

text-shadow:5px 5px 10px gray
<span style="text-shadow:5px 5px 10px gray">测试文字</span>

text-shadow: 5px 5px 2px #222, 30px 30px 2px #555, 50px 50px 2px #888
<span style="text-shadow: 5px 5px 2px #222, 30px 30px 2px #555, 50px 50px 2px #888">测试文字</span>
</body>
</html>